Heat trap



April 26, 1938. F. w. ANDERSON HEAT TRAP Filed Dec. 5, 1936 Patented Apr. 26,- 1938 UNITED STATES HEAT TRAP Frank W. Anderson,

Roslindale, Mass, assignor of one-half to Orr J. Palmer, Quincy, Mass. Application December 5, 1936, Serial No. 114,425

5 Claims.

This invention relates to improvements in hot water or steam traps, and the principal purpose of the invention is to provide a durable, efl'lcient and economical trap having a thermostatically operated valve arranged to open or close abruptly, thereby to avoid the wearing or pitting of the valve seat which characterizes the slow-acting valves heretofore used in trapsof this type.

Further objects reside in the novel construction and mode of operation of the thermostatic element and valve of the improved trap as hereinafter described and pointed out in the appended claims.

A recommended form of a hot water trap embodying this invention and adapted particularly for the heat system of a laundry, is illustrated in the accompanying drawing, in which:

Fig. 1 is a side view looking toward the cover of the improved trap, partly broken away and partly in section;

Fig. 2 is a bottom view of 1; v

Fig. 3 is a detail section on line 3-3 of Fig. 1; and

the trap as shown in ment of the trap shown in Figs. 1 and 2.

In the particular embodiment chosen for the purpose of illustration, the trap comprises a casing having body casting ll providing a chamber for hot water or steam, and having inlet and outlet ports 12 and 20, respectively, and a plugged, optional inlet It in one side; a cover I 5 secured upon the flanged open side of the body or casing by bolts or cap screws l6, and sealed by a gasket IT; a valve mounted at the outlet; and a thermostatic control for the valve, carried by the side or'cover I5. The trap is preferably mounted for use in the position shown in Fig. l, but it will be evident that it may be suitably mounted at any convenient angle.

The valve consists of a metal tube or sleeve l8 screwed upon a threaded end [9 of a nipple 20 mounted in the outlet and having a relatively small opening 2| therethrough which may terminate in a flaring mouth 22 at the outer end of the nipple; and a rod or stem 23 slidable in the tube and formed with a pointed or conical tip 24 adapted to engage the valve seat at the inner end of the opening 2|. Radial ports 25 in the tube l8 lead to a chamber 39 between the valve tip and the valve seat when the valve is open as shown in Fig. 1, so that water may flow through the ports 25 and outlet orifice 2|.

The opposite end of the valve stem 23 is provided with a peripheral flange or nut 26 which is slidably received in the slot 21 of a block 28 to which the bimetallic strips 29 of the thermostatic control are attached by Welding or by screws 30 as best shown in Figs. 3 and 4. The opposite ends of the parallel thermostatic strips 29 are Fig. 4 is a plan view .of the thermostatic elecoiled about and attached by welding or by screws 3! to a spindle 32 which passes inwardly through a stufling box 33 on the cover l5. It will be understood that the number and width of the resilient bimetallic strips 29 may be varied as desired.

A lever or arm 34 is fastened to the outwardly projecting end of the spindle 32'and an adjustment screw 35, under spring tension, connects the arm 34 with a stationary support 36 afiixed to the cover, so that the position of the spindle and, consequently, the'position of the coiled thermostat and the valve may be manually varied by operating the adjusting screw when desired.

The adjustment is preferably such that the trap valve will automatically open at approximately F. and automatically close at F., undera water pressure of 100 pounds or higher. In case of necessity, however, the valve may be manually opened or closed without removing thecover l5, by moving the lever 34 or rod 3l-connected to its outer end. Such manual operation of the valve is particularly important when it is desired to produce a blow through of the-hot water after the trap andheat system have been inactive, in order to afford quick heat'in the system. i

It will be understood that any rotative movement of the spindle 32 changes the position of the thermostatic link with the valve stem 23 and tends to move the valve tip toward or from its seat; and that variations in temperature of the water within the trap automatically change the position of the expansible thermostatic strips and thus tend to open or close the valve. For example, if the coiled thermostat as shownin Fig. 1 is caused to expand by higher temperature conditions, the valve stem will move toward closing position.

As the valve starts to close under influence of I the thermostat, the pressure in the innerend of the outlet orifice 2i immediately drops, and the valve stem is snapped against its seat by the differential in water pressure inside and outside the valve which overcomes any resistance of the resilient thermostat. Conversely, when a drop in the Water temperature causes the thermostat to contract and thus tends to move the valve 011 its seat, the initial movement of the valve stem allows hot water to enter chamber 39 through the tube ports 25, thus raising the pressure in the inner end of the orifice 2| and equalizing the pressure on the opposite ends of the valve stem, and allowing the stem to be quickly moved to fully open position under the action of the resilient thermostat. In the latter case, the initial contraction of the thermostatic element tends to build up a torque in the resilient strips 29, owing Y to closingof the valve, the V substantially-less than ythat of the sleeve and equalized, as aforesaid; sothat the valve springs ends: of,,said orifice, when the valve tip 24' is" slightly ofi seat in opening orfclosing move- [high pressure hotgw'ater system 'for which the "traps herein illustrated to fully open position." l

The rapid action of thevalve results from the provision of therelatively long and narrow outletyorifice 2| which, combination with the "apertured sleeve 1 8,'ensuresthat a differential in pressure is created betweenlthe inner and outer ment.' 'It will be observed that the bore of the orifice 2| is substantially smaller vthanthat of thesleeve or tube 18, and that the length of the orifice is very muchgreaterthan the diameter of its bore, the proportion being approximately ten to one in the size illustrated. 'Such arrangement creates a-rapid drop in pressure at the in ner; end of the, orifice when the valve is closing,

' and a rapidrbuildup of pressure, atthat point it V mg andextending inwardly fromv-the valve seat; l

when the valveisopening;

1 VA quick-acting valve constructed as ab'ovedescribed is especially desirable andlefiicient in 'a was devised, for it elimi- "natesithe wear and corrosion of the valveseat resuIting-iromthe rush of waterljpast the par tially, open elementsjoi a advantage, is also achieved when a trap of the character. indicated is employed in a 1 steam sys tem,'if or a quick-acting valve avoidslprolonged' wearing action of the; steam on the valve seat; i and this invention is intended-foriuse with steam a's'well'as hot,water,;as aforesaid; ,t I

iThegimproved trap not only provides a;p OSi:-f 1 tive,j ;durable and 3g}; afiordsleconomies in manufacture 7 owing to the t f 'simplicityiof the parts andtheease oi assembly. 7 ItqwilLbe noted, ior ex'ample; :that alli-of .the mov-v ableielements ;;are' carried by the trap "cover 5 fined in the following claims. al-claim: V ",LqAheat quick-acting valve, but. also and iexcept'for theivalviestemfl l maybe mounted as a unit'on the cover-beforegitisscrewed; to V 'the'body l I.

l It will be apparent that the structural details offthe trap hereinillustrated and described may .be varied to-suit particular 'purposes'without departing from the essence of this invention as deprising; a casing, provided with" inlet 7 and outlet lportsgthe outlet havinga relatively long and nar-' v T rowldischarge orifice theinner end of which con- 7 f stitutes-ayalve seat af'sleeve disposed within the Leasing andextnding inwardly from the zval ve t seat and having radial ports adjacent, said seat,

a valvelstem slidable 'in said'lsleeve and'having a tip engageable with the valve'seat to close the discharge orifice, and 'a-,-,thrmostatic e1ement prising a casing provided with inlet'andjoutletr 7 connected to "theQvalve stem and automatically changing conditions of tempera operative; under turewithin the casing to" cause rapid openingor bore of.-the orifice being the lengthof the orifice being very much greater influence of'saidthermostatic element.

aivalve seat, a sleeve'disposed within the casing and extending inwardly; from the valve seat;'and

7 element. I

ports; thev outlet having slow acting valve, This v valve stem;

the spindle. on

static member 'coiledaboutfand; attached to, said.

trap off the character described comports, the latter having a "valve seat at its'inner end a-valve having a tip spindle :extendingj into cover, and; a resilient described com-l relatively narrow 'dis'-.

through the cover, and al'resilient thermostatic m'ember coiled about and attached to said spindle and connected at its opposite end to the 'valve stem for automatically opening or closing the valve under changing temperature conditions, and manuallyoperable adjusting means located on the outside of the cover iorlrotating the spindle to vary the position of the coiled thermostatic 3. Aheat trap'oi prising a casing provided'with inlet and outlet a relatively narrow fdischarge orifice, the inner ,end ofqwhichconstitutes 'a 'valve 'seat; a, sleeve disposed within" the; case and having radial' ports adjacent said seat a the character described como V 15 v alve' stem slidableinsaid sleeve and having a tip t charge. orifice;

connectediat -its oppositeend to "the spindle and for automatically. opening or closingengageable with the valve seat to close. the dis+ I a spindle-extending into thecas- 7 ing throughzthe cover, and a resilient thermo-I static member coiled aboutnand. attached to said '25 V t 1 the valve under changing temperature condig tiofns andamanually operable means connected to l 30 l v theouter side of the cover ior ;ro-' tating' the, spindle to, move thethermostatic mem perature within the casing.

prising a casing provided withinlet 'and' putlet ports the outlet having a relatively narrowdis charge orifice; thejinneri end' ofwhich con tutes agvalve; seat; a sleeve disposed}; withi her and open-the valveeirrespectivefof the tern-y V ,casing'and extending inwardly from the" valve seat, and having radial-ports adjacent ,saidseat 'a valve stem slidablein'said sleeve and having a tip engageable with-thesvalve seat-to close the j j discharge; orifice,;a, spindlefiextendinginto-the. f

the valve under changing temperaturecondit 'tions, an-arm connected to theouter endvof the l 7' 7 spindle and adapted to rotate vthe;spindleto vary the position of thethermcstaticflmember,an adjustingrzscrewgfor-setting the arm in predeterv V mined positiomthe arm-being manually "movable to, rotate' the spindle and open; the valve; irree spective'of the setting of-the'adjusting screwor V the temperature within the casing 25.A heat trap oi the character described, come,

discharge orifice "andia engageable withxsaidxseat to closethe' outlet/Qathe casing through I the thermostatic. member ecoiled to said spindle and cone about and attached operablevv adjusting means 

